Knitting machine and method



Fell 28, 1956 P. w. BRlsTow KNITTING MACHINE AND METHOD B Sheets-Sheet lFiled OCT.. 18, 1951 ATTORNEYS.

Feb. 28, 1956 Filed Oct. 18, 1951 P. w. BRlsTow 2,736,177

KNITTING MACHINE AND METHOD 8 Sheets-Sheet 2 /AW//fa ATTORNEYS.

Feb. 2s. 1956 P, W, BRISTOW 2,736,177

KNITTING MACHINE AND METHOD Filed Oct. 18, 1951 8 Sheets-Sheet 3ATTORNEYSA KNITTING MACHINE AND METHOD 8 Sheets-Sheet 4 Filed Oct. 18,1951 IIHII ATTORNEYS.

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KNITTING MACHINE AND METHOD Filed Oct. 18, 1951 8 Sheets-Sheet 5 mma/MATTORNEYS.

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KNITTING MACHINE AND METHOD Filed 001,. 18, 1951 8 Sheets-Sheet 6ATTORNEYS.

Feb. 28, 1956 P. w. BRlsTow KNITTING MACHINE AND METHOD Filed Oct. 18, l.95l

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Feb. 28. 1956 P. w. BRxsTow KNITTING MACHINE AND METHOD 8 Sheets-Sheet 8Filed Oct. 18, 1951 F/G, l2,

fx s im n fa N R United States Patent O f' KNITTING MACHINE AND METHODPaul W. Bristow, deceased, late of Laconia, N. H., by Mildred S.Bristow, executrix, Laconia, N. H., assignor to Scott & Williams,Incorporated, Laconia, N. H., a corporation of Massachusetts ApplicationOctober 18, 1951, Serial No. 251,868

24 Claims. (Cl. 6614) This invention relates to knitting machines of thesuperposed cylinder type and, particularly, to improvements thereinhaving to do with the two-feed knitting of heels and toes. l I

superposed cylinder knitting machines are well-known and areparticularly designed for the knitting of stockings having rib tops suchas l X l rib and legs and insteps which are provided with so-calledbroad ribs or with decorative structure of links-links type. In suchmachines, the cylinders closely approach each other for the transfer andproper support of needles and the machines are provided with arcuatesinkers which are supported inside the circle of needles, being arrangedto be projected between the needles by cams which are also locatedinside the needle circle. In view of the fact that there is a cage ofneedles existing during the formation of ribbed fabric, it is impossibleto provide yarn feeding or controlling devices having portions insidethe needle circle. In order to insure proper handling of yarn duringreciprocatory knitting of heels and toes, so-called bluff sinkers areprovided which are controlled by the sliders of needles raised or pickedout of action to prevent improper entrapment of yarn.

It is recognized that two-feed knitting is highly advantageous from thestandpoint of rapidity of production and, in particular, that two-feedreciprocatory knitting of heels and toes is advantageous in view of thefact that the pro duction rate of the machine is particularly loweredduring reciprocatory knitting. Two-feed knitting of heels and toes isalso desirable because no eyelets are then produced due to starting anddiscontinuing a second feed.

Various problems arise, however, in attempting to secure two-feedreciprocatory knitting in machines of the superposed cylinder type. Theproblems involve the matters of feeding of yarns, the guarding of needlelatches, the control of sinkers, and the operation of bluff sinkers. Aswill become more apparent hereafter, these various matters tend toconflict with each other in several fashions. For example, the provisionof desirable latch guards is inhibited by the Sinker operations and, inturn, requires lspecial feeding of the yarns, particularly the auxiliaryyarn inasmuch as the main and auxiliary yarn feeds must be closetogether in order to leave proper space for picking during thereciprocatory knitting of heels and toes. Sinker operation, andparticularly the proper operation of bluif sinkers, also involvesinterference if the usual types of relationships of operating cams areinvolved.

The general object of the present invention is to provide a knittingmachine of the superposed cylinder type which is capable of properlyknitting stockings having two-feed heels and toes consistently with thesecuring of normal broad rib or links-links structure in the leg andwith the provision of conventional welt and top formations. Inaccordance with the present invention, eyelets are avoided in thestarting and discontinuing the operation of a second feed. Subsidiaryobjects of the present invention are concerned with proper controls ofsink- 2,736,177 Patented Feb. 28, 1956 fice ers during reciprocatoryknitting, there being provided for this purpose circularly shiftablesinker cams arranged to change the phases of sinker operations duringforward and reverse strokes of the needle cylinders.

Other objects of the invention are concerned with the provision ofsuitable latch guarding arrangements and, in particular, with thefeeding of yarns so as to supplement the latch guards in insuring thatneedles will not fail to take yarns to form stitches.

Still another object of the invention has to do with various details ofthe interrelationships of the machine parts to provide propercooperation thereof.

These and other objects of the invention particularly relating todetails of construction and operation will become apparent from thefollowing description, read in conjunction with the accompanyingdrawings, in which:

Figure l is a vertical section through the portions of the machineadjacent to the contiguous ends of the cylinders;

Figure 2 is an elevation of the same portions of the machine;

Figure 3 is a fragmentary horizontal section taken generally above thelower cylinder;

Figure 4 is an enlargement of certain of the parts within the circleshown in construction lines in Figure 3;

Figure 5 is a perspective View showing the control of a narrowing pickerwhen positioned to raise a single needle during a reciprocation;

Figure 6 is a view similar to Figure 5 but showing the narrowing pickerwhen positioned to raise two needles during a reciprocation;

Figure 7 is a fragmentary elevation, partly in section, showing inparticular the means for controlling oscillation of the sinker cams;

Figure 8 is a vertical section takenon the plane the trace of which isindicated at 8-8 in Figure 7;

Figure 9 is a vertical section taken on the plane the trace of which isindicated at 9--9 in Figure 7;

Figure 10 is a fragmentary elevation viewed from the plane the trace ofwhich is indicated at 10-10 in Figure 7;

Figure 11 is an inside development of the cams and other elements actingon the sliders and sinkers, the cams acting on the sinkers beingillustrated in two positions at X and Y, the position at X showing thesesinker cams in their clockwise position, while the position at Y showsthem in their counterclockwise position;

Figure 12 is a diagram showing a portion of the inside of a heel sutureof a stocking knit by the machine; and

Figure 13 is a diagrammatic elevation of a typical sock such as may beknit by the machine.

The present knitting machine is of the well-known superposed cylindertype including lower and upper cylinders 2 and 4, respectively, whichare slotted for the reception of lower sliders 6 and upper sliders 8which control needles 10. The lower sliders 6 are provided with upperbutts 12 and lower butts 14 while the upper sliders 8 are provided withlower butts 16 and upper butts 18. These butts are differentiated inconventional fashion so as to be selective for transfer purposes and forthe knitting of heels and toes. The particular butt arrangements will bereferred to in greater detail hereafter. Verge =bits 20 carried by the-upper cylinder assembly cooperate with needles which are located in theupper cylinder for the production of rib stitches. Sinkers 22. areassociated with the lower cylinder 2 and are provided with butts 24which are arranged to be acted upon by suitable cams .generallyindicated at 30 and 32 and as hereafter more fully described. AssociatedwithA the sinkers which are in the sole series of needles are blusinkers 26 provided with the usual shoulders or ledges 28 and withprojections 29 which are engaged by laterally extending lugs on lowersliders for the general purposes described in detail, for example, inthe patent to Bentley et al. 1,986,317, dated January l, 1935. Thesebluff sinkers are provided with suitable butts also arranged to be actedupon by the sinker cams.

The cams and 32 are supported by the sinker cam sleeve 34 which isgenerally stationary but, in the present machine, is adapted to havesmall oscillatory movements during reciprocatory knitting for purposeshereafter detailed.

At its lower end the sleeve 34 is provided with a projecting portion 36which is arranged to be abutted by a pair of adjustable screws 38carried by an arm 4t) secured to a hub 42 which is journalled forrocking movements upon a stud 44. The hub 42 is provided with an arm 45which is acted upon by a spring 46 normally urging it against anadjustable stop 48. The arm 40 is provided with an. ear 50 through whichpasses a rod 52 provided with collars 5.4 and 56 on opposite sides ofthe ear 50. The rod 52 is pivoted at its forward end in a lever 58 whichis secured to a shaft 6i) carrying an arm 62 arranged to be acted uponby a cam 64 carried by the usual gear 66 which mounts the crank pin 68actuating the connecting rod 7i)` for the purpose of rocking the usualgear segment which imparts oscillatory movements to the needle cylinderduring the knitting of heels and toes. The gear 66 makes a completerevolution for each complete reciprocation of the needle cylinders.Another arm 72 secured to the shaft is provided with a pin 74 with whichcooperates a lever 76 pivoted to the frame at 77 and normally urged in acounterclockwise direction, as viewed in Figure 9, bya spring 78. To thelever '76 there is adjustably secured an extension 81) adapted to beengaged by the forward end of a lever 84 which, as is conventional,carries a pin S2- arranged to disconneet the clutch 88 which controlsthe rotation of the usual fabric take-up rollers and fabric-receivingcan by the shaft 90, the lever 84 for this purpose being rocked throughthe medium of an arm in conventional fashion from the main cam drum ofthe machine. As is usual in machines of this type, the fabric-receivingcan rotates with the needle cylinders during circular knitting of thelegs and foot portions of stockings but is maintained stationary, bydisengagement of clutch 88, during reciprocatory knitting of heels andtoes. The forward end of the arm 84 is arranged to engage the extension80 of lever 76 so as to rock it against stop 86, against the action ofspring 78, during reciprocatory knitting.

During circular knitting, when the fabric-receiving can is rotating, theparts occupy the position illustrated in dash-dot lines in Figure 9 sothat the lever 76 engages beneath pin 74 and holds the shaft 60 in theposition which it assumes when rocked outwardly by cam 64. ln otherwords, during rotary knitting, the shaft 6l) remains stationary while,during reciprocatory knitting of heels and toes, the arm 62 follows thecam 64 to impart oscillating movements to the sinker cam sleeve 34, Aswill become apparent hereafter, the movements of the sinker camsproduced about the vertical axis of the cylinders are opposite thedirections of oscillation of the cylinders; when, for example, theneedle cylinder is rotating counterclockwise, the sinker cams areshifted to a clockwise position and held there by cam 64 during thecontinuation of the counterclockwise stroke; on the other hand, during aclockwise stroke, the sinker cams are held in a counterclockwiseposition limited by stop 48 under the action of spring 46, this positionbeing assumed when the cam 64 is not acting upon arm 62,

It will be evident that the latching of shaft 60 during 7 rotaryknitting could be controlled in other fashion from the main cam drum,but the controlling connections to the fabric-receiving can provide aconvenient control, being shifted at the same times as those at whichlatching is to be effected or released.

Reference may now be made to the cam development constituting Figure 1l.The forward stitch cam at the main feed which acts upon the upper buttsof sliders in the lower cylinder is shown at 92. The correspondingreverse stitch cam at the main feed is at 94. The forward and reverselower stitch cams at the auxiliary feed are respectively shown at 96 and98. During circular knitting, the upper butts 12 of the lower cylindersliders are lowered by stitch cam 92 and are raised to clearing level bythe successive actions of cams 100 and 1112. They then pass below stitchcam 96, taking yarn at the second or auxiliary feed, and are cleared bythe following cams 104 and 106. During reverse reciprocating strokes theupper butts of the lower sliders are depressed by stitch cam 98 andtheir needles seize yarn at the auxiliary feed. The stitches thus drawnare cleared by the successive actions of cams 168 and 110, and the lowerslider butts 12 then pass under the stitch cam 94 to cause their needlesto take yarn at the main feed, the drawn stitches being then cleared bythe successive actions of cams 112 and 114. 1t will be noted that thereare only three knitting points at which the lower cylinder needles areat their lower stitch-drawing positions, the center stitch cam serving,by edge 92, as the run down stitch cam for the main feed and, by edge98, as the reverse stitch cam for the auxiliary feed. This enables theentire set of stitch cams to be located compactly within half thecircumference of the cylinders; but difficulties then arise in feedingthe auxiliary yarn which are solved as hereafter described.

Cams 116 and 118, which are arranged to engage only long upper butts 12,are mounted and controlled for axial movements between the positionsillustrated at 116 and 118 and the positions illustrated at 11.6' and118', respectively, the latter positions being assumed during heel andtoe knitting.

A dropper picker 120 located as shown, and arranged to be moved into andout of active position in conventional fashion, is arranged to engagethe upper butts of lower cylinder sliders so as to lower threesuccessive sliders upon each stroke of the needle cylinders during heeland toe widening. Raising pickers are provided at 122 and 124 and areadapted to raise selectively' either one or two lower cylinder slidersupon each reciprocatory stroke, the full line positions of these pickerswhich are illustrated being those positions in which they arerespectively adapted to raise two sliders on each stroke, while thedotted positions illustrated at 122 and 124' are the positions whichthey assume as upper butts 12 ride beneath them.

The various cams acting on the lower butts of upper cylinder sliderswill now be described.

At 126 there is illustrated the forward stitch cam at the main feed,while at 128 there is shown the forward stitch cam at the auxiliaryfeed. As upper cylinder sliders move toward the left in Figure 11, theyare raised by the action of cam 126 so that their associated needlestake yarn at the main feed. They are then depressed by the successiveactions of cams 130 and 132 to effect clearing of the stitches. Cams 134and 128 then again raise the upper sliders to cause their associatedneedles to take yarn at the auxiliary feed and the stitches thus drawnare cleared by the successive actions of cams 136 and 138,

the cam 140 then raising the upper cylinder sliders for the approach tothe main feed stitch cam 126.

Conventional transfer actions of the needles between the two cylindersare eected by the usual cams 142, 144 and 146. The cam 142 raises thelower sliders at desired times by action upon their upper butts 1,2 forthe production of links-links work. The cam 144 acts upon lower butts 14which are selectively arranged in different lengths to provide f ortransfers for the production of 1 x 1 ribs or broad ribs, the cam 144having three selective positions for this purpose. The upper transferearnl 1,4 6 which acts upon the upper butts 18 of the upper cylindersliders, which butts are of three lengths for the production of l x lrib fabric, broad rib fabric, or half-round broad rib fabric, has fourselective positions for engaging the butts of these various lengths plusan inactive position. At 148 there is illustrated the conventional camfor providing, by control of the needles, for proper release andyseizure of the needles by the respective sliders. The transferoperations involved in the present machine are essentially conventionaland need not be further described.

As will become more apparent hereafter, the present invention isconcerned to a considerable extent with the provision of latch guardsfor the needles. An upper main feed latch guard is shown at 150, beingprovided at its lower edge with cut-outs 152 and 154 for the movement oflatches at required times. A lower main feed latch guard is shown at 156which lies closer to the needle cylinder than the guard 150 where theyjoin. An upper auxiliary feed latch guard is provided at 158 and has apair of cutouts 160 and 162 between which there is a lower` edge 163which has the position and form illustrated most clearly in Figure 1. Alower auxiliary feed latch guard at 164 has an upper edge at 165 whichis positioned relatively to the edge 163, just referred to, asillustrated in Figure l, the edge 163 lying closer to the needlecylinder than the edge 165. This lower latch guard 164 is also providedAwith a bevelled trailing end shown at 167 (Figures 3 and 4).

Yarns are fed at the main feed from the conventional interchangeablefingers of which one illustrated at 155 is shown as feeding a main yarnA in Figure 2. As is usual these yarn fingers are arranged to feed mainyarns selectively with proper overlaps, the yarns being controlled byconventional clamps and cutters.

An auxiliary yarn B passes downwardly from. the supply and is engaged bya conventional spring-controlled take-up 168 which takes up slack duringreciprocatory knitting. From the loop 168 of take-up 170 the yarn Bpasses through a hook 166 and thence passes, being at times selectivelyengaged by, a wire hook 172 which is carried by a plate 174 pivoted at176 to the frame and normally urged counterclockwise, as viewed inFigure 2, by a spring 178 to a position limited by an adjustable stop180. A rod 182, arranged to be acted upon by connections to the main camdrum of the machine, is arranged to swing the plate 174 and hook 172clockwise as viewed in Figure 2 against the action of spring 178.

A wire guide 184 which is carried by the bracket 185 which supports thelatch guard 164 has the shape illustrated in the various figures and inparticular has corners at 184 and 184" which, as hereafter described indetail, take part in the proper guidance of the auxiliary yarn B.

The picker 122 is carried by an arm pivoted to the frame at 127, thepicker being urged toward a lower position by the action of a spring131. The picker 124 is similarly carried by an arm pivoted at 129 andurged to move the picker to its lower position by a spring 133.

As was stated above, the pickers 122 and 124 are selectively adapted toraise either one or two lower sliders in a cylinder stroke. To providefor this action, there are provided a pair of cam plates 135 and 147.The cam plate 135 is pivoted at 137 and connected by link 139 to one endof a lever 141 pivoted to the frame at 143, the other end of which leveris connected by link 145 to the cam plate 147 which is pivoted to theframe at 149. A Bowden wire 153 is connected to the lever 141 and isarranged to be acted upon by the main cam drum of the machine. A spring151 normally urges the lever 141 in a counterclockwise direction, asviewed in plan, and this spring tends to move both cam plates 135 and147 inwardly to act on the picker supporting levers to move therespective pickers to intermediate positions so that each will raiseonly one slider at a time the butt of the slider to be'raised engagingthe lower step of the picker. When, however, the Bowden wire 153 ispulled, the cam plates 135 and 147 release the pickers to theirlowermost positions in which each is adapted to raise two sliders at atime, the butt of the Ileading slider to be raised engaging the upperstep of the picker while the lower step engages and raises the butt ofthe second slider to be raised.

At the lower portion of Figure 11, there are indicated in developed formthe two positions X and Y alternativein developed form the two positionsX and Y alternativeillustration X of these sinker cams, they are shownin the positions which they occupy relative to the slider cams duringrun-down operation, i. e., counterclockwise rotation of the cylindersduring rotaryknitting and counterclockwise reciprocating movement of thecylinders, while in the lower illustration Y they are shown in thepositions assumed during reverse reciprocation strokes. The cam 30 isshown as provided with knock-over portions at 186, 188, 190 and 192. Aswill be evident, the portions 186 and 188 respectively act when stitchesare drawn by the stitchcams 92 and 96, whereas the portions 190 and 192act when stitches are drawn by the cams 98 and 94. Sinker .withdrawalsare effected by the projections 194, 196 and 198 of the lower cam 32,the upper cam 30 being correspondingly relieved at the positions ofthese projections. In the lower illustration the same cam portions areillustrated but in positions wherein their numerals are respectivelyprimed. v

The starting of a stocking and welt formation is carried out asdescribed in Bristow application, Serial No. 241,- 434, filed August 1l,1951. The present invention is not concerned with these operations and,hence, they need not be described in detail. A two-feed 1 x 1 rib topmay be formed in conventional fashion, the sliders in the upper andlower cylinders following the paths already described. Following thisrib top, transfer of sliders is effected in conventional fashion andknitting of the leg takes place for Vthe formation of broad ribstructure or links-links structure at two feeds, the sliders againtaking the paths described above.

Following the completion of the leg, heel formation takes place as willbe presently described in detail. Following this, transfer of sliders isagain effected to produce a plain sole and a broad rib or links-linksinstep, the sole and instep being knit at both feeds while, again, thesliders take the paths already described. The toe may then be knit asdescribed in detail hereafter and, following this, rotary knitting isresumed with all of the needles in the lower cylinder to providetwo-feed loopers waste courses.

As already indicated, the invention is primarily concerned with theformation of two-feed heels and toes and the operations involved thereinwill now be described.

The lower butts of the upper sliders and the upper butts of the lowersliders are long in the instep series and short in the sole series.v

As a preliminary to heel formation, all of the needles in the heel orshort butt section in the upper cylinder are transferred to the lowercylinder and the long butt instep sliders in the lower cylinder areraised to inactive level above the knitting cams by the positioning ofcams 116 and 118 in the positions illustrated at 116 and 118. The instepneedlesvaccordngly hold the stitches last drawn by them in both theupper and lower cylinders, failing to knit at both feeds as the lastcircular stroke takes place. At the end of this stroke, the short buttsof the lower sliders extend from a point just beyond the end of the riseof cam 106 counterclockwise to la position above the cam 112 but shortof the picker 122.

The pickers 122 and 124 are now in their lowermost positions by reasonof withdrawals of cams and 147.

On the first reverse reciprocating stroke, the leading and second shortbuttsare engaged and raised by picker 124. The remainingshort butts passover the cam 96 and the cam 102,' and then pass'down the stitch cam 98to produce drawing of the'yarn at the second feed. They then rise overcamsf108 and 110 to clear the drawn stitches and pass under cam 94 toeffect drawing of the yarn at the main feed. They then rise over cams112 and 114 and the leading short butt winds up at a position above thecam 104 short of the picker 124. The trailing short butt at the end ofthis reverse reciprocation starts from the position above the cam 112,heretofore mentioned, and winds up in a position beyond the top of therise of cam 114. As a result, all of the short butt sliders controllingneedles which took yarns are raised to clearing position.

On the next forward stroke, the now leading short butt and the nextfollowing one are picked up by picker 122, while the needles associatedwith the remaining short butts take yarns at both feeds, passing firstover cams 94 and 110, then drawing yarn at the main feed in passingunder cam 92, being cleared by the actions of cams 100 and 162, thendrawing yarn at the auxiliary feed by passing under cam 96 and beingcleared by rising over cams 104 and 106, the trailing short butt wind`ing up at a position beyond the rise of cam 106 while the leading shortbutt which passed through the knitting wave winds up `at a positionshort of the picker 122.

During counterclockwise or run-down movement of the sliders, the sinkercams occupy the positions illustrated at X in Figure l1. During suchoperation the cams 186 and 188 are respectively properly positioned 'fto provide knock-over at the main and auxiliary feeds. Cam 1&6 is thenjust beyond the lower end of the stitch cani edge 92 and cam 188 is justbeyond the lower end of stitch cam 96.

Coincidentally with beginning of reciprocatory knit ting, follower 62 isreleased to follow cam 64. During reverse reciprocation, follower 62 isnot engaged by cam S4 and, as a result, spring 46 effects acounterclockwise` shift of the sinker cams to position Y. As a result,

the positions 183', 136', 190 and 192 are respectively attained by thecams 188, 186, 190 and 192. It will be noted that, under theseconditions, the gap at 198' is in the circumferential position of picker124, a position previously occupied by the knock-over cam 188A 1t may benoted that the actual shifting movements of the sinker cams occur aslong butt sliders are passing the feed points so that the sinker camsare properly positioned when the sinker' movements are significant; i.e. when the short butt sliders are passing through their knitting waves.

At gap 198' the sinker hooks are projected outwardly of the needlecircle well beyond the Shanks of the needles so that as the leadingshort butt'sliders are picked up and the bluff sinkers are raised, yarnwill not be trapped between the sinker hooks and the bluff sinker ledges2S. lf the sinker cams remained in the run-down position X, knock-overcam 188 would have been at the position of picking and the rise of thebluff sinker might well have trapped yarn. It may be noted that thearrangement for shifting the sinker cams is provided as a result of thepicking of two sliders simultaneously since it is the yarn extendingbetween the two picked needles which would be trapped by the bluffsnkers if the cams were not shifted.

When thc sinker cams occupy thc position Y, the knock-over cam positionsare 199' and 192 in proper relationship to the stitch cams 93 and 94,respectively. ln this case, also, there is a knock-over cam, at 192', ina positionwhich would interfere with the picking at 122 resultingy inpossible entrapment of yarn. However, when the sinker cams are in theposition X, the gap at 194 will be in the circumferential position ofthe picker 122 so that trapping of the yarn at the time of picking isavoided.

in the widening operation, the cams 135 and 147 are moved to theiractive positions to locate the pickers 122. and 1,24 so as to raise onlya single short butt in each stroke. On each forward Stroke, the Pickel122 Will raise the leading active short butt of the short butt seriesand the dropping pickel- 120, now lowered to active position, will pickdown the first three inactive short butts trailing the remaining activeshort butts, the dropper, after moving downwardly in its pickingmovement, remaining inactive during the passage of the inactive shortbutts following those picked down and preceding the long butts, all ofthe long butts, and then the inactive short butts trailing the longbutts. This movement brings beyondy the dropper the last of the lattergroup of short butts which is inactive. On cach reverse reciprocationstroke, a similar action occurs, again resulting in picking up of asingle leading active short butt and picking down of three short butts,following the series of active short butts.

The resulting stitch structure will be that of Figure l2 in which themain and auxiliary feed yarns are distinguished by shading. lt should benoted that during the reciprocatory knitting the courses consist of twosuccessive courses of main feed yarn followed by two successive coursesof auxiliary feed yarn, and so on, the last yarn knit during a stroke inone direction being the rst knit in the stroke in the oppositedirection. in further explanation of the stitch structure shown inFigure l2, it may he noted that thc needles picked down follow inknitting sequence those which follow the one picked up in the samestroke.

In the foregoing, no particular mention has been made of the matter ofyarn feeds, but it may now be pointed out how these feeds areaccomplished consistently with the proper guarding of latches.

In a superposed cylinder machine in which two-feed knitting of heels andtoes is not accomplished, and in which a yarn fed at an auxiliary feedpoint is fed only during rotary knitting, there is no particulardifficulty involved in providing for proper guarding of latches ofneedles in the upper cylinder. But in a machine in which the auxiliaryfeed is active during reciprocatory knitting, the proper presentation ofthe auxiliary yarn to the needles is diihcult to accomplish consistentlywith proper latch guarding inasmuch as the yarn shifts back and forthbetween successive reciprocating strokes and the ends of the latches ofthe lower cylinder needles must be kept below the yarn lead while theends of the latches of upper cylinder needles must be kept above theyarn lead, except during clearing. The problem involved is to get thelower cylinder needle latches inside a lower guard and at approximatelythe same position to get the upper cylinder latches either inside oroutside an upper guard, with proper control in either case, while stillleaving ample space between the two guards for the yarn to switch backand forth freely. Latch guards alone are not sufficient for control ofthe latches since latch throw and bounce are not predictable and sinceclearance must be provided for the knock-over actions of the sinkers andtheir proper rctractions. in particular, the sinkers must be positionedso as not to interfere with the latch guards and the latch guards canonly be located where interfering sinker movements would not berequired.

By shifting the lead of the auxiliary yarn under different conditions,including feed below the upper edge of the lower guard, the yarn itselfassists the latch guards in control of upper cylinder needle latches sothat whether or not such a latch may come inside or outside the upperlatch guard, it will still be above the yarn lead and cannot close whilethere is yarn being fed to lower cylinder needles going down the secondfeed stitch cam. By provision of sinker cams as described the lowersection of a second feed latch guard is made possible.

Referring particularly to Figures l, 2, 3, 4 and ll the matters of yarnfeeding and latch guarding may be made clear. During rotary knitting theauxiliary yarn B is in the B1 position illustrated in Figure 4 (whichposition is also illustrated in Figure 2), the hook 172 being positioncdby spring 17S to draw the auxiliary yarn downwardly so that itapproaches the needles from a level be-- low the top edge 165 of thelower latch guard 164 at the 9 auxiliary feed and extends about thebevelled trailing end 167 of this latch guard.

At the main feed, the needles in the lower cylinder take yarn in passingdown the cam 92 and their latches close beyond the trailing end of thelatch guard 156, the opening at 152 in the upper main feed latch guardpermitting latch closing of upper cylinder needles to take place though,as will be pointed out, this opening provides an unnecessarily largeclearance for this purpose and is primarily provided for a differentpurpose. The needles in the upper cylinder approach guard 156 at clearedlevel at which their latches are prevented from closing by the emptysliders in the lower cylinder. As they are raised by the action of cam140, the ends of their latches pass from behind guard 156 to behindguard 150, this passage occurring smoothly because guard 156 is closerto the cylinders than guard 150. The needles in the upper cylinder thentake yarn at the main feed in moving up the cam 126. As the needles inthe upper cylinder reach the opening 152, their latches may drop but ifthey do so they will drop upon the main yarn, trapping the same.

As the lower cylinder needles approach the second feed and rise up overcams 100 and 102, their latches open and are trapped behind the guard158. As their sliders are lowered preliminarily by cam 103 beforepassing down cam 96, the second feed yarn is above the ends of theirlatches so that they cannot close without trapping this yarn. Duringlowering by cam 103, the lower ends of the latches pass from behindguard 158 to a position behind guard 164, and this passage is insuredsince edge 163 is closer to the cylinder than edge 165.

As the upper cylinder needles are lowered by cams 130 and 132, theirlatches will be opened by the loops on their shanks and will be heldopen behind guard 164 until the previous stitches are cleared.

As the upper cylinder needles are raised by their sliders riding up cam134 their latches pass from behind latch guard 164 near its beveled end167. These latches may then go behind guard 158 at 163, or in front ofthis guard. The yarn trailing olf the. beveled end 167 of guard 164insures the yarns getting below the end of the latches of these upperneedles so that as the latches close at cut-out 162, or fall because ofpassing in front of guard 158, they fall on the yarn and guide it intotheir hooks at the proper time.

During reciprocation, since all needles are in the lower cylinder, onlythe guarding of lower cylinder latches need be considered.

It may be here remarked that the guarding of picked and instep needles(whether in the upper or lower cylinder) is effected by thecorresponding empty sliders. The empty sliders in the upper cylinderopposite the heel needles guard these when they are at cleared level.

During forward reciprocatory strokes the events which occur are similarto those involved in rotary knitting, but the feed of yarn at theauxiliary feed is somewhat different, the hook 172 being out of actionand the yarn being led, as indicated at B2 from the corner 184' of thewire loop 184. Under these conditions, it is led from a higher level soas to be approximately at the level of the opening between the upper andlower latch guards at the auxiliary feed so as to pass freely back andforth between them during changes in the directions of the reciprocatingstrokes. During heel and toe knitting yarn is fed only to the lowercylinder needles and thus` the yarn can be fed high above the ends ofthe latches of these needles since there are no latches of uppercylinder needles requiring the yarn to be fed low to them; and thismakes it possible to feed the yarn high enough to pass freely betweenthe latch guards as it reciprocates, feeding to needles knitting rst inone direction, then in the other. l

During the reverse reciprocating strokes, the .auxiliary yarn lead is asindicated at B3, the yarn approaching the needles from the corner 184"of the loop 184. Un-- der these conditions, it approaches the needlessomewhat higher than during reciprocation in the forward direction. Thisinsures that the yarn will be above the lower ends of the latches as thesliders rise over cam 102. The latches of the active needles are open atcleared level and are guarded initially at this level by the empty uppercylinder sliders. The latches then pass behind the upper guard 158 whichholds them open until, when they close, they will be in position to trapthe auxiliary yarn. The opening at 152 in the upper latch guard at themain feed is to permit the latches to open as the needles rise over cams108 and 110.

From the foregoing, it will be observed that the yarn feeding, latchguarding and sinker operations are rendered consistent withreach otherfor the production of twofeed heels and toes as well as two-feed legs ofstockings.

There is illustrated in Figure 13 a typical sock produced by the machineheretofore described. The welt region 4is indicated at C followed by arib top D and leg E. The rib top and legare knit two-feed with resultingincrease in rate of production. Just prior to formation of the heel, ribneedles at the rear of the sock are transferred to the lower cylinderfor the formation of a plainrear portion F. The heel G is knit two-feed,as described above. The instep and sole H and I, respectively, are thenknit twofeed, the sole being shown as a plain sole knit with all of theneedles in the lower cylinder. Following this the instep needlespreviously knitting ribs are transferred to the lower cylinder for theformation of a number of courses at K of plain two-feed type. The toe isthen knit two-feed as indicated at L and this is followed by theknitting of two-feed plain courses at M to provide the loopers wastecourses. v

It will be evident that two feed heels and toes may be knit utilizingvarious matters of the present invention but with the same variations asdescribed in the patent to Robert H. Lawson No. 2,440,280. Gussets mayalso be provided in accordance with the patent of Grothey and Lawson,No. 2,590,008, issued March 18, 1952.

It will, of course, be evident that with proper pattern controlsprovided for the sliders the needles may be transferred selectivelybetween the upper and lower cylinders for the formation of links-linkswork instead of the broad rib structure.

What is claimed is:

l. A knitting machine comprising a needle cylinder, means for impartingreciprocatory movements to said cylinder, needles slidable in saidcylinder, means for feeding yarns to needles at two feed points, camsfor moving moving needles to form stitches at both of said feed pointsduring reciprocations in both directions, sinkers cooperating with theneedles in the formation of stitches, sinker cams for impartingmovements to the sinkers, and means for effecting for each reciprocationof the needle cylinder a shift of said sinker cams about the cylinderaxis which is opposite the direction of re ciprocation of the needlecylinder.

2. A knitting machine comprising a needle cylinder. means for impartingreciprocatory movements to said cylinder, needles slidable in saidcylinder, means for feeding yarns to needles at two feed points, camsfor moving needles to form stitches at both of said feed points duringreciprocations in both directions, means for picking out of action apair of adjacent needles during each reciprocation of the needlecylinder, sinkers cooperating with the needles in the formation ofstitches, sinker cams for imparting movements to the sinkers, and meansfor effecting for each reciprocation of the needle cylinder a shift ofsaid sinker cams about the cylinder axis which is opposite the directionof reciprocation of the needle cylinder.

3. A knitting machine comprising superposed needle cylinders, means forimparting reciprocatory movementsv to said cylinders, needles slidablein saidcylinder's, means for feeding yarns to needles at two feedpoints, cams for moving needles to form stitches at both of said feedpoints during reciprocations in both directions, sinkers cooperatingwith the needles in the formation of stitches, sinker cams for impartingmovements to the sinkers, and means for effecting for each reciprocationof the needle cylinders a shift of said sinker cams about the axis ofthe cylinders which is opposite the direction of reciprocation of theneedle cylinders.

4. A knitting machine comprising superposed needle cylinders, means forimparting reciprocatory movements to said cylinders, needles slidable insaid cylinders, means for feeding yarns to needles at two feed points,cams for moving needles to form stitches at both of said feed pointsduring reciprocations in both directions, means for picking out ofaction a pair of adjacent needles during each reciprocation of theneedle cylinders, sinkers co operating with the needles in the formationof stitches, bluff sinkers associated with needles which are arranged toknit during reciprocation, sinker cams for imparting movements to thesinkers and bluff sinkers, and means for effecting for eachreciprocation of the needle cylinders a shift of said sinker cams aboutthe axis of the cylinders which is opposite the direction ofreciprocation of the needle cylinders.

5. A knitting machine comprising a needle cylinder, means for impartingreciprocatory movements to said cylinder, needles slidable in saidcylinder, means for feeding yarns to needles at two points, cams formoving needles to form stitches at both of said feed points duringreciprocations in both directions, sinkers cooperating with the needlesin the formation of stitches, sinker cams for imparting movements to thesinkers, means for effect ing for each reciprocation of the needlecylinder a shift of said sinker cams about the cylinder axis which isopposite the direction of reciprocation of the needle cylinder, andmeans for maintaining during rotary knitting said sinker cams in theposition assumed for a forward reciprocation.

6. A knitting machine comprising superposed needle cylinders, means forimparting reciprocatory movements to said cylinders, needles slidable insaid cylinders, means for feeding yarns to needles at two feed points,cams for moving needles to form stitches at both of said feed pointsduring reciprocations in both directions, sinkers cooperating with theneedles in the formation of stitches, sinker cams for impartingmovements to the sinkers, means for effecting for each reciprocation ofthe needle cylinders a shift of said sinker cams about the axis of thecylinders which is opposite the direction of reciprocation of the needlecylinders, and means for maintaining during rotary knitting said sinkercams in the position assumed for a forward reciprocation.

7. A knitting machine comprising superposed needle cylinders, means forimparting reciprocatory movements to said cylinders, needles slidable insaid cylinders, means for feeding yarns to needles at two feed points,earns for moving needles to form stitches at both of said feed pointsduring reciprocations in both directions, means for picking needles outof action, and means selectively controlling said picking means toproduce, alternatively, the picking of a pair of adjacent needles duringeach reciprocation of the needle cylinders or the picking of a singleneedle during each reciprocation of the needle cylinders.

8. A knitting machine comprising superposed needle cylinders, means forimparting reciprocatory movements to said cylinders, latch needlesslidable in said cylinders, means for feeding a yarn to needles at afeed point, cams for moving needles to form stitches at said feed pointduring reciprocations in both directions, and upper and lower latchguards at said feed point, said guards having respective lower and-upperedges providing between them a restricted passage for said yarn, saidyarn feeding means including means for guiding said yarn for freemovement through said passage during changes of direction of thereciprocatory movements of said needle cylinders.

9. A knitting machine comprising superposed needle cylinders, means forimparting reciprocatory movements to said cylinders, latch needlesslidable in said cylinders, means for feeding a yarn to needles at afeed point, cams for moving needles to form stitches at said feed pointduring reciprocations in both directions, and upper and lower latchguards at said feed point, said guards having respective lower and upperedges providing between them a restricted passage for said yarn, saidyarn feeding means including means providing different points ofapproach of the yarn to the needles during the opposite reciprocatorymovements of said needle cylinders.

l0. A knitting machine comprising superposed needle cylinders, means forimparting reciprocatory movements to said cylinders, latch needlesslidable in said cylinders, means for feeding a yarn to needles at afeed point, cams for moving needles to form stitches at said feed pointduring reciprocations in both directions, and upper and lower latchguards at said feed point, said guards having respective lower and upperedges providing between them a restricted passage for said yarn, saidyarn feeding means including means for guiding said yarn in paths ofapproach to the needles during both directions of reciprocation of theneedle cylinders such that the approaching yarn will prevent closure ofneedle latches after clearing.

ll. A knitting machine comprising superposed needle cylinders, means forimparting rotary movements to said cylinders, latch needles slidable insaid cylinders, means for feeding a yarn to needles at a feed point,cams for moving needles to form stitches at said feed point, and upperand lower latch guards at said feed point, said guards having respectivelower and upper edges providing between them a restricted passage forsaid yarn, said yarn feeding means including means for guiding said yarnto approach the needles across an edge of one of said latch guards.

12. A knitting machine comprising superposed needle cylinders, means forimparting rotary movements to said cylinders, latch needles slidable insaid cylinders, means for feeding a yarn to needles at a feed point,cams for moving needles to form stitches at said feed point, and upperand lower latch guards at said feed point, said guards having respectivelower and upper edges providing between them a restricted passage forsaid yarn, said yarn feeding means including means for guiding said yarnto approach the needles across an edge of one of said latch guards, sothat said yarn will prevent closure of needle latches after the needlespass the last mentioned latch guard.

13. A knitting machine comprising superposed needle cylinders, means forimparting rotary and reciprocatory movements to said cylinders, needlesslidable in said cylinders, means for transferring needles between saidcylinders, means for feeding a yarn to said needles at each of a pair offeed points, cams at said feed points for controlling the needles toform stitches at both of said feed points, and means for effectingproduction of two feed knitting concurrently with narrowing and wideningto produce fabric pockets.

i4. A knitting machine comprising superposed needle cylinders, means forimparting rotary and reciprocatory movements to said cylinders, needlesslidable in said cylinders, means for transferring needles between saidcylinders, means for feeding a yarn to said needles at each of a pair offeed points, cams at said feed points for controlling the needles toform stitches at both of said feed points, and means for effectingproduction of two feed knitting concurrently with narrowing and wideningto produce fabric pockets, the last mentioned means including pickingdevices for removing from action two needles upon each reciprocatorystroke of the needle cylinders during narrowing and for restoring toaction three needles and for removing from action one needle upon eachreciprocatory stroke of the needle cylinders during widenlng.

15. A knitting machine comprising superposed needle cylinders, means forimparting rotary and reciprocatory movements to said cylinders, needlesslidable in said cylinders, means for transferring needles between saidcylinders, means for feeding a yarn to said needles at each of a pair offeed points, cams at said feed points for controlling the needles toform stitches at both of said feed points, and means for effectingproduction of two feed knitting concurrently with narrowing and wideningto produce fabric pockets, the last mentioned means including pickingdevices for removing from action two needles upon each reciprocatorystroke of the needle cylinders during narrowing and for restoring toaction a plurality of needles and for removing from action two less thansaid plurality of needles upon each reciprocatory stroke of the needlecylinders during widening.

16. A knitting machine comprising a needle cylinder, means for impartingreciprocatory movements to said cylinder, needles slidable in saidcylinder, means for feeding yarn to said needles, means for picking outof action a pair of adjacent needles during each reciprocation f of theneedle cylinder, sinkers cooperating with the needles in the formationof stitches, and means for retracting sinkers at the location of saidpicking means.

17. A knitting machine comprising a needle cylinder, means for impartingreciprocatory movements to said cylinder, needles slidable in saidcylinder, means for feeding yarns to needles at two feed points, camsfor moving needles to form stitches at both of said feed points duringreciprocation in both directions, means for picking out of action a pairof adjacent needles during each reciprocation of the needle cylinder,sinkers cooperating with the needles in the formation of stitches, andmeans for retracting sinkers at the location of said picking means.

18. A knitting machine comprising superposed needle cylinders, means forimparting rotary and reciprocatory movements to said cylinders, latchneedles slidable in said cylinders, means for feeding yarns to needlesat two feed points, cams for moving needles to form stitches at both ofsaid feed points during reciprocations in both directions, and latchguards for guarding latches of needles in both the upper and lowercylinders during rotary knitting and for guarding latches of needles inthe lower cylinder during reciprocatory knitting.

1,9. The method of knitting a stocking on an independent needle knittingmachine comprising forwardly and reversely concatenating loops toprovide a leg portion thereof, forming a heel pocket by reciprocatoryknitting of two yarns knit in successive courses during reciprocation ineach direction, forwardly and reversely concatenating loops to provide afoot portion thereof, and forming a toe pocket by reciprocatory knittingof two yarns knit in successive courses during reciprocation in eachdirection.

20. The method of knitting a stocking on an independent needle knittingmachine comprising forwardly and reversely concatenating loops toprovide a leg portion thereof, forming a heel pocket by reciprocatoryknitting of two yarns knit in successive courses during reciprocation ineach direction, forwardly and reversely concatenating loops to provide afoot portion thereof, and forming a toe pocket by reciprocatory knittingof two yarns knit in successive courses during reciprocation in eachdirection, each of said pockets involving, during narrowing, removalfrom action of two needles upon each reciprocation and, during widening,restoration to action of three needles and removal from action of oneneedle upon each reciprocation.

21. The method of knitting a stocking on an independent needle knittingmachine comprising forwardly and reversely concatenating loops toprovide a two feed leg portion thereof, forming a heel pocket byreciprocatory knitting of two yarns knit in successive courses duringreciprocation in each direction, forwardly and reversely concatenatingloops to provide a two feed foot portion thereof, and forming a toepocket by reciprocatory knitting of two yarns knit in successive coursesduring reciprocation in each direction.

22. The method of knitting a stocking on an independent needle knittingmachine comprising forwardly and reversely concatenating loops toprovide a two feed leg portion thereof, forming a heel pocket byreciprocatory knitting of two yarns knit in successive courses duringreciprocation in each direction, forwardly and reversely concatenatingloops to provide a two feed foot portion thereof, and forming a toepocket by reciprocatory knitting of two yarns knit in successive coursesduring reciprocation in each direction, each of said pockets involving,during narrowing, removal from action of two needles upon eachreciprocation and, during widening, restoration to action of threeneedles and removal from action of one needle upon each reciprocation.

23. A knitting machine comprising a needle cylinder, means for impartingreciprocatory movements to said cylinder, latch needles slidable in saidcylinder, means for feeding yarn to said needles, means for picking atleast one needle out of action during each reciprocation of the needlecylinder, sinkers cooperating with the needles in the formation ofstitches, and movable means for retracting sinkers at the location ofsaid picking means during picking actions thereof, said retracting meansbeing at other times ineffective to retract sinkers at the location ofsaid picking means.

24. A knitting machine comprising a needle cylinder, means for impartingreciprocatory movements to said cylinder, needles slidable in saidcylinder, means for feeding yarn to said needles, sinkers having nebscooperating with said needles to form stitches, blulf sinkers associatedwith sinkers having nebs, means for picking at least one needle out ofaction during each reciprocation of the needle cylinder, means effectingmovement of said bluff sinkers concurrently with picking of needles, andmeans for retracting sinkers at the location of said picking means toavoid trapping of yarn between bluff sinkers and associated sinker nebsduring picking.

References Cited in the file of this patent UNITED STATES PATENTS943,230 Pigeon Dec. 14, 1909 1,782,298 Grieve Nov. 18, 1930 1,814,885Aust July 14, 1931 2,237,144 Houseman Apr. 1, 1941 2,313,642 Holmes etal Mar. 9, 1943 2,316,823 Thurston et al Apr. 20, 1943 2,366,405 Holmeset al Ian. 2, 1945 2,385,056 Bromley et al Sept. 18, 1945 2,398,785Grothey Apr. 23, 1946 2,412,248 Bristow Dec. 10, 1946 2,417,479Fregeolle Mar. 18, 1947 2,440,280 Lawson Apr. 27, 1948 2,440,333Fregeolle Apr. 27, 1948 2,531,073 Miller Nov. 21, 1950 2,576,962McDonough Dec. 4, 1951 2,590,008 Grothey et al Mar. 18, 1952

